The present invention is directed generally to a radiolucent orthopedic drill chuck which displaces the drill bit sufficiently away from the orthopedic drill that x-rays may be directed axially of the bit without interference by the drill for prompt and precise alignment and drilling.
Although the critical applications for the present invention are diverse, its conception and prototypic clinical trials have involved intramedullary nails. In this country alone, annual tibia surgeries include approximately twenty-three thousand closed reductions and one hundred eleven thousand open reductions. Femur fractures result annually in approximately thirty-three thousand closed reductions and one hundred thirty-one thousand open reductions. For femur fractures, an elongated intramedullary nail is inserted through the center of the bone from an incision in the hip whereupon the nail is stabilized by a single screw inserted through the bone and nail at an angle to the axis of the nail. It has long been a problem to then accurately drill holes aligned with the holes at the distal end of the nail for the interlocking screws.
The current techniques include various free hand techniques as well as techniques using various stationary metal devices. Whereas a fluoroscope is used to assist with proper positioning of the drill, all of these techniques have in common the necessity for removing the fluoroscopic image while drilling. The problem inherent with all of these techniques therefore is that they in fact require blind drillings.
In one manual technique, a large incision is made near the distal end of the nail to expose the bone. The surgeon manipulates an awl to mark the drilling site on the bone with the aid of a fluoroscopic screen. The surgeon gets radiated while positioning the awl. The awl is then set by pounding it against the bone. Alternately, the holes may be drilled percutaneously by positioning the awl to mark the skin, after which the awl is removed and a drill is directed toward the bone through the marked spot on the skin. In either event, the double step of first marking the drilling location with an awl and then moving the awl and inserting a drill increases the chances for error over and above the inherent difficulty of blind drilling.
Certain of the positioning devices afford six degrees of freedom of movement but these require much education on the techniques of using the machine and still result in blind drilling.
Olerud, et al., U.S. Pat. No. 4,625,718 discloses an aiming apparatus for a wire drill. Whereas this devise enables live action sighting, it has several shortcomings which are believed to be resolved by the present invention. First, the Olerud apparatus is awkward for a surgeon to use since it has two handles on both sides of the fluoroscopic beam. Since the head of the x-ray machine is generally positioned about ten inches from the drilling site, it is awkward to reach in and manipulate both handles simultaneously. It requires the drill to be positioned at a right angle to its normal drilling position so that the drill is pushed sideways in an unfamiliar manner during use. Secondly, the metal around the opening of the Olerud, et al., device is radio opaque which is a big disadvantage for sighting. Finally, the Olerud device rotates a wire, not the actual drill bit. Since wire burns bone, it is not a good idea to drill bone with it. Furthermore, since the diameter of the wire is much smaller than a drill bit, it is very difficult to accurately center the wire within the larger diameter nail openings. If the wire opening is eccentrically positioned, a hollow drill bit following the wire will strike the nail rather than be directed through the distal hole as intended.
Accordingly, a primary object of the invention is to provide a radiolucent orthopedic drill chuck which displaces the drill bit from the radio opaque drill for live sighting of the drill bit during the operation.
Another object is to provide a radiolucent orthopedic chuck which protects the surgeon's hand from exposure to the fluoroscopic sighting beam.
Another object is to provide a radiolucent orthopedic chuck which is lightweight, simple in construction and readily usable without special instruction.
Another object is to provide a radiolucent orthopedic chuck which enables the drilling of a hole for an interlocking screw to be quickly and accurately performed thereby reducing trauma to the patient and x-ray exposure of the surgeon.
Another object is to provide a radiolucent orthopedic chuck which is substantially entirely radiolucent but for the drilling bit to afford optimum sighting in use.
Another object is to provide a radiolucent orthopedic chuck which is simple and rugged in construction, economical to manufacture and efficient in operation.